In a paper machine, a pulp suspension (or slurry) is passed into a head-box which extrudes it through a thin, horizontal slit across the full machine width on to a moving, endless wire mesh (or screen). A mixture of gravity and suction remove water in this “wire section” (or sheet formation section) of the paper machine so that the pulp fibers spread and consolidate to form a sheet on top of the wire mesh.
Subsequently, this sheet of wet paper is squeezed in a series of presses, where its water content is further reduced, and then routed around a series of heated drums where drying takes place. Throughout its passage from the headbox to the drying cylinders, various types of wire mesh or fabric belts support the paper web. After drying, some papers may undergo surface treatments, such as sizing or calendaring (smoothing). The finished paper is finally wound onto a reel.